bgp_snmp.c

大名鼎鼎的路由器源码。程序分ZEBRA、OSPFRIP等3个包。程序框架采用一个路由协议一个进程的方式

/* BGP4 SNMP support
   Copyright (C) 1999, 2000 Kunihiro Ishiguro

This file is part of GNU Zebra.

GNU Zebra is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

GNU Zebra is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Zebra; see the file COPYING.  If not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */

#include <zebra.h>

#ifdef HAVE_SNMP
#include <asn1.h>
#include <snmp.h>
#include <snmp_impl.h>

#include "if.h"
#include "log.h"
#include "prefix.h"
#include "command.h"
#include "thread.h"
#include "smux.h"

#include "bgpd/bgpd.h"
#include "bgpd/bgp_table.h"
#include "bgpd/bgp_aspath.h"
#include "bgpd/bgp_attr.h"
#include "bgpd/bgp_route.h"
#include "bgpd/bgp_fsm.h"

/* BGP4-MIB described in RFC1657. */
#define BGP4MIB 1,3,6,1,2,1,15

/* BGP TRAP. */
#define BGPESTABLISHED			1
#define BGPBACKWARDTRANSITION		2	

/* Zebra enterprise BGP MIB.  This variable is used for register
   OSPF MIB to SNMP agent under SMUX protocol.  */
#define BGPDMIB 1,3,6,1,4,1,3317,1,2,2

/* BGP MIB bgpVersion. */
#define BGPVERSION			      0

/* BGP MIB bgpLocalAs. */
#define BGPLOCALAS			      0

/* BGP MIB bgpPeerTable. */
#define BGPPEERIDENTIFIER                     1
#define BGPPEERSTATE                          2
#define BGPPEERADMINSTATUS                    3
#define BGPPEERNEGOTIATEDVERSION              4
#define BGPPEERLOCALADDR                      5
#define BGPPEERLOCALPORT                      6
#define BGPPEERREMOTEADDR                     7
#define BGPPEERREMOTEPORT                     8
#define BGPPEERREMOTEAS                       9
#define BGPPEERINUPDATES                     10
#define BGPPEEROUTUPDATES                    11
#define BGPPEERINTOTALMESSAGES               12
#define BGPPEEROUTTOTALMESSAGES              13
#define BGPPEERLASTERROR                     14
#define BGPPEERFSMESTABLISHEDTRANSITIONS     15
#define BGPPEERFSMESTABLISHEDTIME            16
#define BGPPEERCONNECTRETRYINTERVAL          17
#define BGPPEERHOLDTIME                      18
#define BGPPEERKEEPALIVE                     19
#define BGPPEERHOLDTIMECONFIGURED            20
#define BGPPEERKEEPALIVECONFIGURED           21
#define BGPPEERMINASORIGINATIONINTERVAL      22
#define BGPPEERMINROUTEADVERTISEMENTINTERVAL 23
#define BGPPEERINUPDATEELAPSEDTIME           24

/* BGP MIB bgpIdentifier. */
#define BGPIDENTIFIER                         0

/* BGP MIB bgpRcvdPathAttrTable */
#define BGPPATHATTRPEER                       1
#define BGPPATHATTRDESTNETWORK                2
#define BGPPATHATTRORIGIN                     3
#define BGPPATHATTRASPATH                     4
#define BGPPATHATTRNEXTHOP                    5
#define BGPPATHATTRINTERASMETRIC              6

/* BGP MIB bgp4PathAttrTable. */
#define BGP4PATHATTRPEER                      1
#define BGP4PATHATTRIPADDRPREFIXLEN           2
#define BGP4PATHATTRIPADDRPREFIX              3
#define BGP4PATHATTRORIGIN                    4
#define BGP4PATHATTRASPATHSEGMENT             5
#define BGP4PATHATTRNEXTHOP                   6
#define BGP4PATHATTRMULTIEXITDISC             7
#define BGP4PATHATTRLOCALPREF                 8
#define BGP4PATHATTRATOMICAGGREGATE           9
#define BGP4PATHATTRAGGREGATORAS             10
#define BGP4PATHATTRAGGREGATORADDR           11
#define BGP4PATHATTRCALCLOCALPREF            12
#define BGP4PATHATTRBEST                     13
#define BGP4PATHATTRUNKNOWN                  14

/* SNMP value hack. */
#define INTEGER ASN_INTEGER
#define INTEGER32 ASN_INTEGER
#define COUNTER32 ASN_COUNTER
#define OCTET_STRING ASN_OCTET_STR
#define IPADDRESS ASN_IPADDRESS
#define GAUGE32 ASN_UNSIGNED

/* Declare static local variables for convenience. */
SNMP_LOCAL_VARIABLES

/* BGP-MIB instances. */
oid bgp_oid [] = { BGP4MIB };
oid bgpd_oid [] = { BGPDMIB };

/* IP address 0.0.0.0. */
static struct in_addr bgp_empty_addr = {0};

/* Hook functions. */
static u_char *bgpVersion ();
static u_char *bgpLocalAs ();
static u_char *bgpPeerTable ();
static u_char *bgpRcvdPathAttrTable ();
static u_char *bgpIdentifier ();
static u_char *bgp4PathAttrTable ();
/* static u_char *bgpTraps (); */

struct variable bgp_variables[] = 
{
  /* BGP version. */
  {BGPVERSION,                OCTET_STRING, RONLY, bgpVersion,
   1, {1}},
  /* BGP local AS. */
  {BGPLOCALAS,                INTEGER, RONLY, bgpLocalAs,
   1, {2}},
  /* BGP peer table. */
  {BGPPEERIDENTIFIER,         IPADDRESS, RONLY, bgpPeerTable,
   3, {3, 1, 1}},
  {BGPPEERSTATE,              INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 2}},
  {BGPPEERADMINSTATUS,        INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 3}},
  {BGPPEERNEGOTIATEDVERSION,  INTEGER32, RONLY, bgpPeerTable,
   3, {3, 1, 4}},
  {BGPPEERLOCALADDR,          IPADDRESS, RONLY, bgpPeerTable,
   3, {3, 1, 5}},
  {BGPPEERLOCALPORT,          INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 6}},
  {BGPPEERREMOTEADDR,         IPADDRESS, RONLY, bgpPeerTable,
   3, {3, 1, 7}},
  {BGPPEERREMOTEPORT,         INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 8}},
  {BGPPEERREMOTEAS,           INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 9}},
  {BGPPEERINUPDATES,          COUNTER32, RONLY, bgpPeerTable,
   3, {3, 1, 10}},
  {BGPPEEROUTUPDATES,         COUNTER32, RONLY, bgpPeerTable,
   3, {3, 1, 11}},
  {BGPPEERINTOTALMESSAGES,    COUNTER32, RONLY, bgpPeerTable,
   3, {3, 1, 12}},
  {BGPPEEROUTTOTALMESSAGES,   COUNTER32, RONLY, bgpPeerTable,
   3, {3, 1, 13}},
  {BGPPEERLASTERROR,          OCTET_STRING, RONLY, bgpPeerTable,
   3, {3, 1, 14}},
  {BGPPEERFSMESTABLISHEDTRANSITIONS, COUNTER32, RONLY, bgpPeerTable,
   3, {3, 1, 15}},
  {BGPPEERFSMESTABLISHEDTIME, GAUGE32, RONLY, bgpPeerTable,
   3, {3, 1, 16}},
  {BGPPEERCONNECTRETRYINTERVAL, INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 17}},
  {BGPPEERHOLDTIME,           INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 18}},
  {BGPPEERKEEPALIVE,          INTEGER, RONLY, bgpPeerTable,
   3, {3, 1, 19}},
  {BGPPEERHOLDTIMECONFIGURED, INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 20}},
  {BGPPEERKEEPALIVECONFIGURED, INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 21}},
  {BGPPEERMINASORIGINATIONINTERVAL, INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 22}},
  {BGPPEERMINROUTEADVERTISEMENTINTERVAL, INTEGER, RWRITE, bgpPeerTable,
   3, {3, 1, 23}},
  {BGPPEERINUPDATEELAPSEDTIME, GAUGE32, RONLY, bgpPeerTable,
   3, {3, 1, 24}},
  /* BGP identifier. */
  {BGPIDENTIFIER,             IPADDRESS, RONLY, bgpIdentifier,
   1, {4}},
  /* BGP received path attribute table. */
  {BGPPATHATTRPEER,           IPADDRESS, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 1}},
  {BGPPATHATTRDESTNETWORK,    IPADDRESS, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 2}},
  {BGPPATHATTRORIGIN,         INTEGER, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 3}},
  {BGPPATHATTRASPATH,         OCTET_STRING, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 4}},
  {BGPPATHATTRNEXTHOP,        IPADDRESS, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 5}},
  {BGPPATHATTRINTERASMETRIC,  INTEGER32, RONLY, bgpRcvdPathAttrTable,
   3, {5, 1, 6}},
  /* BGP-4 received path attribute table. */
  {BGP4PATHATTRPEER, IPADDRESS, RONLY, bgp4PathAttrTable,
   3, {6, 1, 1}},
  {BGP4PATHATTRIPADDRPREFIXLEN, INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 2}},
  {BGP4PATHATTRIPADDRPREFIX,  IPADDRESS, RONLY, bgp4PathAttrTable,
   3, {6, 1, 3}},
  {BGP4PATHATTRORIGIN,        INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 4}},
  {BGP4PATHATTRASPATHSEGMENT, OCTET_STRING, RONLY, bgp4PathAttrTable,
   3, {6, 1, 5}},
  {BGP4PATHATTRNEXTHOP,       IPADDRESS, RONLY, bgp4PathAttrTable,
   3, {6, 1, 6}},
  {BGP4PATHATTRMULTIEXITDISC, INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 7}},
  {BGP4PATHATTRLOCALPREF,     INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 8}},
  {BGP4PATHATTRATOMICAGGREGATE, INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 9}},
  {BGP4PATHATTRAGGREGATORAS,  INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 10}},
  {BGP4PATHATTRAGGREGATORADDR, IPADDRESS, RONLY, bgp4PathAttrTable,
   3, {6, 1, 11}},
  {BGP4PATHATTRCALCLOCALPREF, INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 12}},
  {BGP4PATHATTRBEST,          INTEGER, RONLY, bgp4PathAttrTable,
   3, {6, 1, 13}},
  {BGP4PATHATTRUNKNOWN,       OCTET_STRING, RONLY, bgp4PathAttrTable,
   3, {6, 1, 14}},
};

static u_char *
bgpVersion (struct variable *v, oid name[], size_t *length, int exact,
	    size_t *var_len, WriteMethod **write_method)
{
  static u_char version;

  if (smux_header_generic(v, name, length, exact, var_len, write_method)
      == MATCH_FAILED)
    return NULL;

  /* Retrun BGP version.  Zebra bgpd only support version 4. */
  version = (0x80 >> (BGP_VERSION_4 - 1));

  /* Return octet string length 1. */
  *var_len = 1;
  return (u_char *)&version;
}

static u_char *
bgpLocalAs (struct variable *v, oid name[], size_t *length,
	    int exact, size_t *var_len, WriteMethod **write_method)
{
  struct bgp *bgp;

  if (smux_header_generic(v, name, length, exact, var_len, write_method)
      == MATCH_FAILED)
    return NULL;

  /* Get BGP structure. */
  bgp = bgp_get_default ();
  if (! bgp)
    return NULL;

  return SNMP_INTEGER (bgp->as);
}

struct peer *
peer_lookup_addr_ipv4 (struct in_addr *src)
{
  struct bgp *bgp;
  struct peer *peer;
  struct listnode *nn;
  struct in_addr addr;
  int ret;

  bgp = bgp_get_default ();
  if (! bgp)
    return NULL;

  LIST_LOOP (bgp->peer, peer, nn)
    {
      ret = inet_pton (AF_INET, peer->host, &addr);
      if (ret > 0)
	{
	  if (IPV4_ADDR_SAME (&addr, src))
	    return peer;
	}
    }
  return NULL;
}

struct peer *
bgp_peer_lookup_next (struct in_addr *src)
{
  struct bgp *bgp;
  struct peer *peer;
  struct listnode *nn;
  struct in_addr *p;
  union sockunion su;
  int ret;

  memset (&su, 0, sizeof (union sockunion));

  bgp = bgp_get_default ();
  if (! bgp)
    return NULL;

  LIST_LOOP (bgp->peer, peer, nn)
    {
      ret = inet_pton (AF_INET, peer->host, &su.sin.sin_addr);
      if (ret > 0)
	{
	  p = &su.sin.sin_addr;

	  if (ntohl (p->s_addr) > ntohl (src->s_addr))
	    {
	      src->s_addr = p->s_addr;
	      return peer;
	    }
	}
    }
  return NULL;
}

struct peer *
bgpPeerTable_lookup (struct variable *v, oid name[], size_t *length, 
		     struct in_addr *addr, int exact)
{
  struct peer *peer = NULL;
  int len;

  if (exact)
    {
      /* Check the length. */
      if (*length - v->namelen != sizeof (struct in_addr))
	return NULL;

      oid2in_addr (name + v->namelen, IN_ADDR_SIZE, addr);

      peer = peer_lookup_addr_ipv4 (addr);
      return peer;
    }
  else
    {
      len = *length - v->namelen;
      if (len > 4) len = 4;
      
      oid2in_addr (name + v->namelen, len, addr);
      
      peer = bgp_peer_lookup_next (addr);

      if (peer == NULL)
	return NULL;

      oid_copy_addr (name + v->namelen, addr, sizeof (struct in_addr));
      *length = sizeof (struct in_addr) + v->namelen;

      return peer;
    }
  return NULL;
}

/* BGP write methods. */
int
write_bgpPeerTable (int action, u_char *var_val,
		    u_char var_val_type, size_t var_val_len,
		    u_char *statP, oid *name, size_t length,
		    struct variable *v)
{
  struct in_addr addr;
  struct peer *peer;
  long intval;
  int bigsize = SNMP_MAX_LEN;
  
  if (var_val_type != ASN_INTEGER) 
    {
      return SNMP_ERR_WRONGTYPE;
    }
  if (var_val_len != sizeof (long)) 
    {
      return SNMP_ERR_WRONGLENGTH;
    }

  if (! asn_parse_int(var_val, &bigsize, &var_val_type,
                      &intval, sizeof(long)))
    {
      return SNMP_ERR_WRONGENCODING;
    }

  memset (&addr, 0, sizeof (struct in_addr));

  peer = bgpPeerTable_lookup (v, name, &length, &addr, 1);
  if (! peer)
    return SNMP_ERR_NOSUCHNAME;

  printf ("val: %ld\n", intval);

  switch (v->magic)
    {
    case BGPPEERADMINSTATUS:
#define BGP_PeerAdmin_stop  1
#define BGP_PeerAdmin_start 2
      /* When the peer is established,   */
      if (intval == BGP_PeerAdmin_stop)
	BGP_EVENT_ADD (peer, BGP_Stop);
      else if (intval == BGP_PeerAdmin_start)
	;			/* Do nothing. */
      else
	return SNMP_ERR_NOSUCHNAME;
      break;
    case BGPPEERCONNECTRETRYINTERVAL:
      SET_FLAG (peer->config, PEER_CONFIG_CONNECT);
      peer->connect = intval;
      peer->v_connect = intval;
      break;
    case BGPPEERHOLDTIMECONFIGURED:
      SET_FLAG (peer->config, PEER_CONFIG_TIMER);
      peer->holdtime = intval;
      peer->v_holdtime = intval;
      break;
    case BGPPEERKEEPALIVECONFIGURED:
      SET_FLAG (peer->config, PEER_CONFIG_TIMER);
      peer->keepalive = intval;
      peer->v_keepalive = intval;
      break;
    case BGPPEERMINASORIGINATIONINTERVAL:
      peer->v_asorig = intval;
      break;